In systems for Wideband Code Division Multiplex Access (WCDMA), the traffic to a user in the system, i.e. a cellular telephony subscriber, can comprise one or more so called flows. The traffic to a subscriber can use channels referred to by the term HSDPA, High Speed Data Packet Access, while the traffic from the subscriber can use channels known as HSUPA, High Speed Uplink Packet Access, also known as EUL, Enhanced Uplink.
In order to avoid congestion in the system, the system should comprise some form of function for flow control in the HSDPA, and preferably also in the EUL. The main purpose of such functions is to adapt the traffic rate on the HSDPA and/or the EUL to suitable bit rates. The present invention is mainly directed towards flow control in the HSDPA.
Flow control of HSDPA as such is known, but known algorithms are, to a great extent, based on aggregated schemes. Such algorithms have a number of drawbacks, among which the following can be mentioned:                when high speed flows encounter different bottlenecks over the transport network, the performance of the aggregate flow-control can be degraded,        the different scheduling policies can not be made independent from the flow control behaviour to the extent which would be desirable,        aggregated flow control can be sensitive to functionality changes in the system.        